Here is the document http://www.montefiore.ulg.ac.be/~kvansteen/GBIO0009-1/ac20092010/Class8/Using%20R%20for%20linear%20regression.pdf -- View this message in context: http://r.789695.n4.nabble.com/lm-function-strange-error-tp4649065p4649080.html Sent from the R help mailing list archive at Nabble.com.